mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race
[linux/fpc-iii.git] / fs / ocfs2 / filecheck.c
blob2cabbcf2f28ee5db19fb4c674c8d55818f7217f4
1 /* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
4 * filecheck.c
6 * Code which implements online file check.
8 * Copyright (C) 2016 SuSE. All rights reserved.
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public
12 * License as published by the Free Software Foundation, version 2.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
20 #include <linux/list.h>
21 #include <linux/spinlock.h>
22 #include <linux/module.h>
23 #include <linux/slab.h>
24 #include <linux/kmod.h>
25 #include <linux/fs.h>
26 #include <linux/kobject.h>
27 #include <linux/sysfs.h>
28 #include <linux/sysctl.h>
29 #include <cluster/masklog.h>
31 #include "ocfs2.h"
32 #include "ocfs2_fs.h"
33 #include "stackglue.h"
34 #include "inode.h"
36 #include "filecheck.h"
39 /* File check error strings,
40 * must correspond with error number in header file.
42 static const char * const ocfs2_filecheck_errs[] = {
43 "SUCCESS",
44 "FAILED",
45 "INPROGRESS",
46 "READONLY",
47 "INJBD",
48 "INVALIDINO",
49 "BLOCKECC",
50 "BLOCKNO",
51 "VALIDFLAG",
52 "GENERATION",
53 "UNSUPPORTED"
56 static DEFINE_SPINLOCK(ocfs2_filecheck_sysfs_lock);
57 static LIST_HEAD(ocfs2_filecheck_sysfs_list);
59 struct ocfs2_filecheck {
60 struct list_head fc_head; /* File check entry list head */
61 spinlock_t fc_lock;
62 unsigned int fc_max; /* Maximum number of entry in list */
63 unsigned int fc_size; /* Current entry count in list */
64 unsigned int fc_done; /* Finished entry count in list */
67 struct ocfs2_filecheck_sysfs_entry { /* sysfs entry per mounting */
68 struct list_head fs_list;
69 atomic_t fs_count;
70 struct super_block *fs_sb;
71 struct kset *fs_devicekset;
72 struct kset *fs_fcheckkset;
73 struct ocfs2_filecheck *fs_fcheck;
76 #define OCFS2_FILECHECK_MAXSIZE 100
77 #define OCFS2_FILECHECK_MINSIZE 10
79 /* File check operation type */
80 enum {
81 OCFS2_FILECHECK_TYPE_CHK = 0, /* Check a file(inode) */
82 OCFS2_FILECHECK_TYPE_FIX, /* Fix a file(inode) */
83 OCFS2_FILECHECK_TYPE_SET = 100 /* Set entry list maximum size */
86 struct ocfs2_filecheck_entry {
87 struct list_head fe_list;
88 unsigned long fe_ino;
89 unsigned int fe_type;
90 unsigned int fe_done:1;
91 unsigned int fe_status:31;
94 struct ocfs2_filecheck_args {
95 unsigned int fa_type;
96 union {
97 unsigned long fa_ino;
98 unsigned int fa_len;
102 static const char *
103 ocfs2_filecheck_error(int errno)
105 if (!errno)
106 return ocfs2_filecheck_errs[errno];
108 BUG_ON(errno < OCFS2_FILECHECK_ERR_START ||
109 errno > OCFS2_FILECHECK_ERR_END);
110 return ocfs2_filecheck_errs[errno - OCFS2_FILECHECK_ERR_START + 1];
113 static ssize_t ocfs2_filecheck_show(struct kobject *kobj,
114 struct kobj_attribute *attr,
115 char *buf);
116 static ssize_t ocfs2_filecheck_store(struct kobject *kobj,
117 struct kobj_attribute *attr,
118 const char *buf, size_t count);
119 static struct kobj_attribute ocfs2_attr_filecheck_chk =
120 __ATTR(check, S_IRUSR | S_IWUSR,
121 ocfs2_filecheck_show,
122 ocfs2_filecheck_store);
123 static struct kobj_attribute ocfs2_attr_filecheck_fix =
124 __ATTR(fix, S_IRUSR | S_IWUSR,
125 ocfs2_filecheck_show,
126 ocfs2_filecheck_store);
127 static struct kobj_attribute ocfs2_attr_filecheck_set =
128 __ATTR(set, S_IRUSR | S_IWUSR,
129 ocfs2_filecheck_show,
130 ocfs2_filecheck_store);
132 static int ocfs2_filecheck_sysfs_wait(atomic_t *p)
134 schedule();
135 return 0;
138 static void
139 ocfs2_filecheck_sysfs_free(struct ocfs2_filecheck_sysfs_entry *entry)
141 struct ocfs2_filecheck_entry *p;
143 if (!atomic_dec_and_test(&entry->fs_count))
144 wait_on_atomic_t(&entry->fs_count, ocfs2_filecheck_sysfs_wait,
145 TASK_UNINTERRUPTIBLE);
147 spin_lock(&entry->fs_fcheck->fc_lock);
148 while (!list_empty(&entry->fs_fcheck->fc_head)) {
149 p = list_first_entry(&entry->fs_fcheck->fc_head,
150 struct ocfs2_filecheck_entry, fe_list);
151 list_del(&p->fe_list);
152 BUG_ON(!p->fe_done); /* To free a undone file check entry */
153 kfree(p);
155 spin_unlock(&entry->fs_fcheck->fc_lock);
157 kset_unregister(entry->fs_fcheckkset);
158 kset_unregister(entry->fs_devicekset);
159 kfree(entry->fs_fcheck);
160 kfree(entry);
163 static void
164 ocfs2_filecheck_sysfs_add(struct ocfs2_filecheck_sysfs_entry *entry)
166 spin_lock(&ocfs2_filecheck_sysfs_lock);
167 list_add_tail(&entry->fs_list, &ocfs2_filecheck_sysfs_list);
168 spin_unlock(&ocfs2_filecheck_sysfs_lock);
171 static int ocfs2_filecheck_sysfs_del(const char *devname)
173 struct ocfs2_filecheck_sysfs_entry *p;
175 spin_lock(&ocfs2_filecheck_sysfs_lock);
176 list_for_each_entry(p, &ocfs2_filecheck_sysfs_list, fs_list) {
177 if (!strcmp(p->fs_sb->s_id, devname)) {
178 list_del(&p->fs_list);
179 spin_unlock(&ocfs2_filecheck_sysfs_lock);
180 ocfs2_filecheck_sysfs_free(p);
181 return 0;
184 spin_unlock(&ocfs2_filecheck_sysfs_lock);
185 return 1;
188 static void
189 ocfs2_filecheck_sysfs_put(struct ocfs2_filecheck_sysfs_entry *entry)
191 if (atomic_dec_and_test(&entry->fs_count))
192 wake_up_atomic_t(&entry->fs_count);
195 static struct ocfs2_filecheck_sysfs_entry *
196 ocfs2_filecheck_sysfs_get(const char *devname)
198 struct ocfs2_filecheck_sysfs_entry *p = NULL;
200 spin_lock(&ocfs2_filecheck_sysfs_lock);
201 list_for_each_entry(p, &ocfs2_filecheck_sysfs_list, fs_list) {
202 if (!strcmp(p->fs_sb->s_id, devname)) {
203 atomic_inc(&p->fs_count);
204 spin_unlock(&ocfs2_filecheck_sysfs_lock);
205 return p;
208 spin_unlock(&ocfs2_filecheck_sysfs_lock);
209 return NULL;
212 int ocfs2_filecheck_create_sysfs(struct super_block *sb)
214 int ret = 0;
215 struct kset *device_kset = NULL;
216 struct kset *fcheck_kset = NULL;
217 struct ocfs2_filecheck *fcheck = NULL;
218 struct ocfs2_filecheck_sysfs_entry *entry = NULL;
219 struct attribute **attrs = NULL;
220 struct attribute_group attrgp;
222 if (!ocfs2_kset)
223 return -ENOMEM;
225 attrs = kmalloc(sizeof(struct attribute *) * 4, GFP_NOFS);
226 if (!attrs) {
227 ret = -ENOMEM;
228 goto error;
229 } else {
230 attrs[0] = &ocfs2_attr_filecheck_chk.attr;
231 attrs[1] = &ocfs2_attr_filecheck_fix.attr;
232 attrs[2] = &ocfs2_attr_filecheck_set.attr;
233 attrs[3] = NULL;
234 memset(&attrgp, 0, sizeof(attrgp));
235 attrgp.attrs = attrs;
238 fcheck = kmalloc(sizeof(struct ocfs2_filecheck), GFP_NOFS);
239 if (!fcheck) {
240 ret = -ENOMEM;
241 goto error;
242 } else {
243 INIT_LIST_HEAD(&fcheck->fc_head);
244 spin_lock_init(&fcheck->fc_lock);
245 fcheck->fc_max = OCFS2_FILECHECK_MINSIZE;
246 fcheck->fc_size = 0;
247 fcheck->fc_done = 0;
250 if (strlen(sb->s_id) <= 0) {
251 mlog(ML_ERROR,
252 "Cannot get device basename when create filecheck sysfs\n");
253 ret = -ENODEV;
254 goto error;
257 device_kset = kset_create_and_add(sb->s_id, NULL, &ocfs2_kset->kobj);
258 if (!device_kset) {
259 ret = -ENOMEM;
260 goto error;
263 fcheck_kset = kset_create_and_add("filecheck", NULL,
264 &device_kset->kobj);
265 if (!fcheck_kset) {
266 ret = -ENOMEM;
267 goto error;
270 ret = sysfs_create_group(&fcheck_kset->kobj, &attrgp);
271 if (ret)
272 goto error;
274 entry = kmalloc(sizeof(struct ocfs2_filecheck_sysfs_entry), GFP_NOFS);
275 if (!entry) {
276 ret = -ENOMEM;
277 goto error;
278 } else {
279 atomic_set(&entry->fs_count, 1);
280 entry->fs_sb = sb;
281 entry->fs_devicekset = device_kset;
282 entry->fs_fcheckkset = fcheck_kset;
283 entry->fs_fcheck = fcheck;
284 ocfs2_filecheck_sysfs_add(entry);
287 kfree(attrs);
288 return 0;
290 error:
291 kfree(attrs);
292 kfree(entry);
293 kfree(fcheck);
294 kset_unregister(fcheck_kset);
295 kset_unregister(device_kset);
296 return ret;
299 int ocfs2_filecheck_remove_sysfs(struct super_block *sb)
301 return ocfs2_filecheck_sysfs_del(sb->s_id);
304 static int
305 ocfs2_filecheck_erase_entries(struct ocfs2_filecheck_sysfs_entry *ent,
306 unsigned int count);
307 static int
308 ocfs2_filecheck_adjust_max(struct ocfs2_filecheck_sysfs_entry *ent,
309 unsigned int len)
311 int ret;
313 if ((len < OCFS2_FILECHECK_MINSIZE) || (len > OCFS2_FILECHECK_MAXSIZE))
314 return -EINVAL;
316 spin_lock(&ent->fs_fcheck->fc_lock);
317 if (len < (ent->fs_fcheck->fc_size - ent->fs_fcheck->fc_done)) {
318 mlog(ML_ERROR,
319 "Cannot set online file check maximum entry number "
320 "to %u due to too many pending entries(%u)\n",
321 len, ent->fs_fcheck->fc_size - ent->fs_fcheck->fc_done);
322 ret = -EBUSY;
323 } else {
324 if (len < ent->fs_fcheck->fc_size)
325 BUG_ON(!ocfs2_filecheck_erase_entries(ent,
326 ent->fs_fcheck->fc_size - len));
328 ent->fs_fcheck->fc_max = len;
329 ret = 0;
331 spin_unlock(&ent->fs_fcheck->fc_lock);
333 return ret;
336 #define OCFS2_FILECHECK_ARGS_LEN 24
337 static int
338 ocfs2_filecheck_args_get_long(const char *buf, size_t count,
339 unsigned long *val)
341 char buffer[OCFS2_FILECHECK_ARGS_LEN];
343 memcpy(buffer, buf, count);
344 buffer[count] = '\0';
346 if (kstrtoul(buffer, 0, val))
347 return 1;
349 return 0;
352 static int
353 ocfs2_filecheck_type_parse(const char *name, unsigned int *type)
355 if (!strncmp(name, "fix", 4))
356 *type = OCFS2_FILECHECK_TYPE_FIX;
357 else if (!strncmp(name, "check", 6))
358 *type = OCFS2_FILECHECK_TYPE_CHK;
359 else if (!strncmp(name, "set", 4))
360 *type = OCFS2_FILECHECK_TYPE_SET;
361 else
362 return 1;
364 return 0;
367 static int
368 ocfs2_filecheck_args_parse(const char *name, const char *buf, size_t count,
369 struct ocfs2_filecheck_args *args)
371 unsigned long val = 0;
372 unsigned int type;
374 /* too short/long args length */
375 if ((count < 1) || (count >= OCFS2_FILECHECK_ARGS_LEN))
376 return 1;
378 if (ocfs2_filecheck_type_parse(name, &type))
379 return 1;
380 if (ocfs2_filecheck_args_get_long(buf, count, &val))
381 return 1;
383 if (val <= 0)
384 return 1;
386 args->fa_type = type;
387 if (type == OCFS2_FILECHECK_TYPE_SET)
388 args->fa_len = (unsigned int)val;
389 else
390 args->fa_ino = val;
392 return 0;
395 static ssize_t ocfs2_filecheck_show(struct kobject *kobj,
396 struct kobj_attribute *attr,
397 char *buf)
400 ssize_t ret = 0, total = 0, remain = PAGE_SIZE;
401 unsigned int type;
402 struct ocfs2_filecheck_entry *p;
403 struct ocfs2_filecheck_sysfs_entry *ent;
405 if (ocfs2_filecheck_type_parse(attr->attr.name, &type))
406 return -EINVAL;
408 ent = ocfs2_filecheck_sysfs_get(kobj->parent->name);
409 if (!ent) {
410 mlog(ML_ERROR,
411 "Cannot get the corresponding entry via device basename %s\n",
412 kobj->name);
413 return -ENODEV;
416 if (type == OCFS2_FILECHECK_TYPE_SET) {
417 spin_lock(&ent->fs_fcheck->fc_lock);
418 total = snprintf(buf, remain, "%u\n", ent->fs_fcheck->fc_max);
419 spin_unlock(&ent->fs_fcheck->fc_lock);
420 goto exit;
423 ret = snprintf(buf, remain, "INO\t\tDONE\tERROR\n");
424 total += ret;
425 remain -= ret;
426 spin_lock(&ent->fs_fcheck->fc_lock);
427 list_for_each_entry(p, &ent->fs_fcheck->fc_head, fe_list) {
428 if (p->fe_type != type)
429 continue;
431 ret = snprintf(buf + total, remain, "%lu\t\t%u\t%s\n",
432 p->fe_ino, p->fe_done,
433 ocfs2_filecheck_error(p->fe_status));
434 if (ret < 0) {
435 total = ret;
436 break;
438 if (ret == remain) {
439 /* snprintf() didn't fit */
440 total = -E2BIG;
441 break;
443 total += ret;
444 remain -= ret;
446 spin_unlock(&ent->fs_fcheck->fc_lock);
448 exit:
449 ocfs2_filecheck_sysfs_put(ent);
450 return total;
453 static int
454 ocfs2_filecheck_erase_entry(struct ocfs2_filecheck_sysfs_entry *ent)
456 struct ocfs2_filecheck_entry *p;
458 list_for_each_entry(p, &ent->fs_fcheck->fc_head, fe_list) {
459 if (p->fe_done) {
460 list_del(&p->fe_list);
461 kfree(p);
462 ent->fs_fcheck->fc_size--;
463 ent->fs_fcheck->fc_done--;
464 return 1;
468 return 0;
471 static int
472 ocfs2_filecheck_erase_entries(struct ocfs2_filecheck_sysfs_entry *ent,
473 unsigned int count)
475 unsigned int i = 0;
476 unsigned int ret = 0;
478 while (i++ < count) {
479 if (ocfs2_filecheck_erase_entry(ent))
480 ret++;
481 else
482 break;
485 return (ret == count ? 1 : 0);
488 static void
489 ocfs2_filecheck_done_entry(struct ocfs2_filecheck_sysfs_entry *ent,
490 struct ocfs2_filecheck_entry *entry)
492 entry->fe_done = 1;
493 spin_lock(&ent->fs_fcheck->fc_lock);
494 ent->fs_fcheck->fc_done++;
495 spin_unlock(&ent->fs_fcheck->fc_lock);
498 static unsigned int
499 ocfs2_filecheck_handle(struct super_block *sb,
500 unsigned long ino, unsigned int flags)
502 unsigned int ret = OCFS2_FILECHECK_ERR_SUCCESS;
503 struct inode *inode = NULL;
504 int rc;
506 inode = ocfs2_iget(OCFS2_SB(sb), ino, flags, 0);
507 if (IS_ERR(inode)) {
508 rc = (int)(-(long)inode);
509 if (rc >= OCFS2_FILECHECK_ERR_START &&
510 rc < OCFS2_FILECHECK_ERR_END)
511 ret = rc;
512 else
513 ret = OCFS2_FILECHECK_ERR_FAILED;
514 } else
515 iput(inode);
517 return ret;
520 static void
521 ocfs2_filecheck_handle_entry(struct ocfs2_filecheck_sysfs_entry *ent,
522 struct ocfs2_filecheck_entry *entry)
524 if (entry->fe_type == OCFS2_FILECHECK_TYPE_CHK)
525 entry->fe_status = ocfs2_filecheck_handle(ent->fs_sb,
526 entry->fe_ino, OCFS2_FI_FLAG_FILECHECK_CHK);
527 else if (entry->fe_type == OCFS2_FILECHECK_TYPE_FIX)
528 entry->fe_status = ocfs2_filecheck_handle(ent->fs_sb,
529 entry->fe_ino, OCFS2_FI_FLAG_FILECHECK_FIX);
530 else
531 entry->fe_status = OCFS2_FILECHECK_ERR_UNSUPPORTED;
533 ocfs2_filecheck_done_entry(ent, entry);
536 static ssize_t ocfs2_filecheck_store(struct kobject *kobj,
537 struct kobj_attribute *attr,
538 const char *buf, size_t count)
540 struct ocfs2_filecheck_args args;
541 struct ocfs2_filecheck_entry *entry;
542 struct ocfs2_filecheck_sysfs_entry *ent;
543 ssize_t ret = 0;
545 if (count == 0)
546 return count;
548 if (ocfs2_filecheck_args_parse(attr->attr.name, buf, count, &args)) {
549 mlog(ML_ERROR, "Invalid arguments for online file check\n");
550 return -EINVAL;
553 ent = ocfs2_filecheck_sysfs_get(kobj->parent->name);
554 if (!ent) {
555 mlog(ML_ERROR,
556 "Cannot get the corresponding entry via device basename %s\n",
557 kobj->parent->name);
558 return -ENODEV;
561 if (args.fa_type == OCFS2_FILECHECK_TYPE_SET) {
562 ret = ocfs2_filecheck_adjust_max(ent, args.fa_len);
563 goto exit;
566 entry = kmalloc(sizeof(struct ocfs2_filecheck_entry), GFP_NOFS);
567 if (!entry) {
568 ret = -ENOMEM;
569 goto exit;
572 spin_lock(&ent->fs_fcheck->fc_lock);
573 if ((ent->fs_fcheck->fc_size >= ent->fs_fcheck->fc_max) &&
574 (ent->fs_fcheck->fc_done == 0)) {
575 mlog(ML_ERROR,
576 "Cannot do more file check "
577 "since file check queue(%u) is full now\n",
578 ent->fs_fcheck->fc_max);
579 ret = -EBUSY;
580 kfree(entry);
581 } else {
582 if ((ent->fs_fcheck->fc_size >= ent->fs_fcheck->fc_max) &&
583 (ent->fs_fcheck->fc_done > 0)) {
584 /* Delete the oldest entry which was done,
585 * make sure the entry size in list does
586 * not exceed maximum value
588 BUG_ON(!ocfs2_filecheck_erase_entry(ent));
591 entry->fe_ino = args.fa_ino;
592 entry->fe_type = args.fa_type;
593 entry->fe_done = 0;
594 entry->fe_status = OCFS2_FILECHECK_ERR_INPROGRESS;
595 list_add_tail(&entry->fe_list, &ent->fs_fcheck->fc_head);
596 ent->fs_fcheck->fc_size++;
598 spin_unlock(&ent->fs_fcheck->fc_lock);
600 if (!ret)
601 ocfs2_filecheck_handle_entry(ent, entry);
603 exit:
604 ocfs2_filecheck_sysfs_put(ent);
605 return (!ret ? count : ret);